code: def test_uu_predict_one():
      algo = knn.UserUser(30)
      algo.fit(ml_ratings)
  
      preds = algo.predict_for_user(4, [1016])
      assert len(preds) == 1
      assert preds.index == [1016]
      assert preds.values == approx([3.62221550680778])
  
imports: from lenskit.algorithms import Recommender
  import lenskit.algorithms.user_knn
  from lenskit.util import clone
  from pathlib import Path
  import logging
  import pickle
  import pandas
  import numpy
  from scipy.sparse import linalg
  from pytest import approx, mark
  import lenskit.util.test
label_desc: Use image node_id 7 for calling a global function with example usage: test_uu_predict_one() without return types